Donald Trump has the presidency. His party has both houses of Congress and, with their help, he has successfully derailed congressional investigations of him. He can count on right-wing media outlets to constantly invent new Hillary Clinton scandals to confuse things, change the topic and exhaust us daily. His war on the independent press has convinced many Americans that fake news is a real thing. Most chilling of all, it’s now clear that about 35 percent of Americans will support him no matter what he does.

In this kind of through-the-looking-glass nightmare, Robert Mueller’s investigation — his very existence — seems like the last vestige of the reality we used to cling to: that justice can still prevail, even against all odds. Monday’s indictments are a victory for the rule of law and bad news for Mr. Trump. We may look back on this moment as the beginning of the end for him.

On the other hand, our worst nightmare may be ahead of us. The usual principles that govern human behavior are completely foreign to Mr. Trump. He will not go quietly. He will find a Justice Department lackey who will fire Mr. Mueller. He will issue pre-emptive pardons to his minions and his family members. He can count on this Congress not to interfere. And he will unleash a typically chaotic counterattack.

But firing Mr. Mueller would sow the seeds of Mr. Trump’s inevitable destruction.

While we celebrate the milestone that the indictments represent, we need to also understand that Mr. Trump and Congress will ensure that Mr. Mueller’s time is not long and that he cannot finish the job for us. Only we, the people — through organized resistance and the election of a very different Congress next year — can do that.

KIM FIELD, PORTLAND, ORE.

To the Editor:

The indictments should send a message to all responsible Republicans. What did the reported millions paid to Paul Manafort buy for the pro-Russia interests? We might start with the changes in the 2016 Republican platform, made at the behest of Donald Trump’s representatives, that softened calls for giving weapons to aid Ukrainian resistance to Russia.

The hijacking of part of the platform of one of our major parties by a foreign power should give all of us pause, especially the members of that party.

RAPHAEL CRYSTALTUSCALOOSA, ALA.

To the Editor:

The indictment of George Papadopoulos shows that the Trump campaign rebuffed his offer to arrange a meeting in Moscow between Donald Trump and Vladimir Putin. When Mr. Papadopoulos persisted, a campaign official sent an email encouraging him to make the trip himself. However, the indictment plainly states, “The trip proposed by defendant Papadopoulos did not take place.”

The indictment doesn’t present evidence that the Trump campaign conducted secret meetings with the Russians. It suggests the opposite.

WILLIAM CASE, WEATHERFORD, TEX.

To the Editor:

As the Trump Jenga tower starts to topple, one has to wonder whether Robert Mueller’s carrot-and-stick approach will prevail over likely promises of presidential pardons.

JAN STRIBULA, SOUTHBURY, CONN.

To the Editor:

With the justifiable anguish over Russian influence on the 2016 election through social media, it is easy to forget the critical shortcomings in our own democracy: the staggering level of gullibility, ignorance and spitefulness without which the Russian (not to mention the domestic) trolls would be only a trivial footnote to the 2016 election. The susceptibility of some voters to such manipulation is a longstanding problem for all democracies.

Further, we forget that we received a taste of the medicine that we have inflicted frequently on the rest of the world, including involvement in coups (Iran, Chile), assassinations or attempts (Congo, Cuba), guerrilla wars (Nicaragua), and the tragic wars in Vietnam and Iraq.

JEFFREY SALZMANPALO ALTO, CALIF.

A version of this article appears in print on , on Page A24 of the New York edition with the headline: The Messages of the Mueller Inquiry. Order Reprints | Today’s Paper | Subscribe

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